This invention pertains to apparatus for installing waistbands in a web comprising apparel that is worn on the body such as disposable diapers.
The presently most popular type of disposable diaper comprises a thin flexible liquid impermeable backing sheet on which a permeable nonwoven sheet is overlayed. An absorbent pad is disposed between the two sheets and the sheets are adhered at their edges to form a unitary article and provide for preventing liquid body exudates from seeping out of the edges of the diaper. Most diapers on the market also have longitudinally extending elastic bands adhered to the sheets on each side of the absorbent pad. These bands cause the diaper to engage the legs of the wearer snuggly so as to prevent leakage along the interface of the nonwoven sheet which is in contact with the body.
It is regarded as desirable to have elasticity in the waist regions of the diaper to create a gentle pressure for inhibiting the diaper from slipping down and for preventing the leakage such as might occur when the wearer is lying down. Various methods and apparatus have been devised for inserting an elastic member in the waistband region. Doing this is problematical because the diapers are formed as a web which is moving longitudinally at a high rate. Any elastic segment that is to be inserted in the waistband area of an individual diaper will extend transversely to the longitudinally moving web and must be deposited in a stretched condition on the web while it is in motion. The invention disclosed herein constitutes a new method and apparatus for inserting transversely extending elastic segments in the waist area of diapers and similar body wearable garments.